Empty-load changeover apparatus in current use has a changeover device mounted to a pipe bracket and a separate load-sensing mechanism provided according to a U.S. Scott Pat. No. 3,671,086, granted June 10, 1972, generally known as an SC-1 valve. This apparatus is much too large and heavy to be mounted on a railway truck, for example, as would be required for the braking system disclosed in the U.S. Engle Pat. No. 4,653,812, granted Mar. 31, 1987. This patent discloses a combined empty-load changeover and load sensing device, but is still much too large and heavy for railway truck mounted brake apparatus including a triple valve and reservoirs.
An object of the present invention is to provide improved empty-load changeover apparatus which substantially obviates one or more of the limitations and disadvantages of the described prior systems.
Another object of the present invention is to provide an improved empty-load valve device that is much lighter and more compact than the prior art systems.
Another object of the present invention is to provide an improved empty-load valve device that is simplified and less expensive to manufacture than the above described prior art devices.